The invention relates to a method for checking tandem-arranged shafts to detect angular and/or parallel offset between the center axes of the shafts, using at least one pair of elements made up of an indicating pointer which is fixed in relation to one of the shafts and is generally parallel to its center axis and of a reference element fixedly attached to the other shaft, in a plurality of angular positions of measurement of the shafts, which correspond to each other from shaft to shaft, for the production of two mutually independent alignment data signals, which respectively correspond, in a manner related to the respective angular position of measurement, to a component of the minimum distance apart of the center axes of the shafts, i.e. the parallel offset, and to a component of the maximum angle between such center axes if crossing each other, i.e. the angular offset, or from which such components may be derived.
In known methods of this type (see the periodical INSTANDHALTUNG, December 1982, published by Verlag Moderne Industrie, Landsberg, Germany, "Die Kunst des Ausrichtens ubernimmt jetzt der Computer" and European patent publication, EP-B1-0 145 745) the alignment data signals are produced at angular positions of measurement, which are angularly spaced from each other by about 90.degree. and values for parallel offset and angular offset are obtained directly from these data. A useful degree of accuracy is obtained, but the known methods are only free of problems or are only able to be used at all, if there is a suitable clearance for the measuring device and the indicating pointer around the shafts. The measuring device, which produces the alignment data signals, necessarily laterally projects from the shafts and furthermore each indicating pointer is necessarily located outside and to the side of the shaft. The measurements are taken in at least three positions of measurement so that the shafts with the measuring device have to be turned through at least 180.degree.. At the positions at which the measuring device is located on the shafts it is necessary for there to be a clearance over this substantial angle around the shafts, and furthermore at least in the angular positions of measurement (which are set in relation to each other) along the length of each indicating pointer there is to be no obstruction between the parts of the measuring device arranged on the two shafts, this also applying if the indicating pointer is in the form of a light beam (see said publication EP-B1- 0 145 745). This condition is frequently not fulfilled in practice and may in fact not be able to be fulfilled.